CORPUS CHRISTI — Eventually, Juan Diaz will have to prove himself. He'll have to prove he can fight — and beat — the best of the best in his weight class in order to complete his comeback.

Saturday night before a crowd of 3,200 at the American Bank Center, the former world lightweight champion from Houston was held to no such standard.

In his first bout since retiring from the ring two years ago, Diaz pounded away at Pipino Cuevas Jr. (15-10, 13 KOs) for the better part of six rounds before earning a technical knockout victory in his comeback fight.

Diaz (36-4, 18 KOs) proved he can still fight, but he also showed he's more than a bit rusty.

“I needed to get this fight out of the way,” said Diaz, 29, who turned pro at 16 and won a world title at age 20. “I felt the ring rust most fighters who have been off talk about.”

Diaz was the aggressor from the opening bell, landing punches at will against Cuevas, the son of the former world champion by the same name.

Referee Mark Calo-oy stopped the bout 55 seconds into the sixth round. Cuevas protested, but his face by that time was a bloody mask.

It only would have gotten worse.

“I got more and more comfortable as the fight wore on,” Diaz said. “I was smothering my punches, though.”

He said he would look at the video of the fight and make a determination as to his next opponent.